<!DOCTYPE html>
<html>

<head>
    <meta charset="UTF-8">
    <title>响应式布局</title>
    <meta name="keywords" content="" />
    <meta name="description" content="" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <style>
        * {
            margin: 0;
            padding: 0;
            text-decoration: none;
            list-style: none;
            font-size: 14px;
            font-family: "微软雅黑";
            text-align: center;
            color: #fff;
        }

        .clear {
            clear: both;
        }

        #header,
        #content,
        #footer {
            margin: 0 auto;
            margin-top: 10px;
        }

        #header,
        #footer {
            margin-top: 10px;
            height: 100px;
        }

        #header,
        #footer,
        .left,
        .right,
        .center {
            background: #333;
        }

        /*通用样式*/
        /*手机*/
        @media screen and (max-width:600px) {

            #header,
            #content,
            #footer {
                width: 400px;
            }

            .right,
            .center {
                margin-top: 10px;
            }

            .left,
            .right {
                height: 100px;
            }

            .center {
                height: 200px;
            }
        }

        /*平板*/
        @media screen and (min-width:600px) and (max-width:960px) {

            #header,
            #content,
            #footer {
                width: 600px;
            }

            .right {
                display: none;
            }

            .left,
            .center {
                height: 400px;
                float: left;
            }

            .left {
                width: 160px;
                margin-right: 10px;
            }

            .center {
                width: 430px;
            }
        }

        /*PC*/
        @media screen and (min-width:960px) {

            #header,
            #content,
            #footer {
                width: 960px;
            }

            .left,
            .center,
            .right {
                height: 400px;
                float: left;
            }

            .left {
                width: 200px;
                margin-right: 10px;
            }

            .center {
                width: 540px;
                margin-right: 10px;
            }

            .right {
                width: 200px;
            }
        }
    </style>
</head>

<body>
    <!--header start-->
    <div id="header">header</div>
    <!--end header-->
    <!--content start-->
    <div id="content">
        <div>left</div>
        <div>center</div>
        <div>right</div>
        <div></div>
    </div>
    <!--end content-->
    <!--footer-->
    <div id="footer">footer</div>
    <!--end footer-->
</body>

</html>